1. Field of the Invention
The invention relates in general to a backlight module, and more particularly to a direct backlight module for a thin-film transistor liquid crystal display.
2. Description of the Related Art
Liquid crystal displays (LCDs) have been widely used as large displays such as screens of desktop computers and small displays such as portable information terminals because LCDs have the characteristics of thin shape, light weight, low power dissipation. However, a LCD is not a self-luminescent display so that a backlight module is required as the light sources.
FIG. 1 shows a conventional direct backlight module. Referring to FIG. 1, a direct backlight module 100 includes a reflective base 110, several lamp tubes 120 and a lamp-supporting frame 130. The lamp tubes 120 are light sources of the direct backlight module 100 and light emitted from the lamp tubes 120 are reflected to a LCD display by the reflective base 110.
The lamp tubes 120 are disposed on the reflective base 110 via several buffer blocks 115 within the lamp-supporting frame 130. In another words, two ends of the lamp tubes 120 are mounted in the buffer blocks 115 separately, and the buffer blocks 115 are covered and enclosed by the lamp-supporting frame 130 so that the lamp tubes can be connected with the lamp-supporting frame 130. Then, the lamp-supporting frame 130 is assembled with the reflective base 110 so that the lamp tubes 120 are further sposed above the reflective base 110.
However, the buffer rubbers 115, as bad conductors of heat, are covered and enclosed by the lamp-supporting frame 130, and heat generated from two ends of the lamp tube 120 is kept and accumulated inside the buffer blocks 115. As a result, the temperature of the whole direct backlight module 100 can be easily raised, and cause the great effect on the luminance performance of the direct backlight module.